From: Peter Hess peter.hess@ph-home.de
[ Upstream commit 3a70dd2d050331ee4cf5ad9d5c0a32d83ead9a43 ]
In FIFO mode were two problems: - RX mode was never handled and - in this case the tx_buf pointer was NULL and caused an exception
fix this by handling RX mode in mtk_spi_fifo_transfer
Fixes: a568231f4632 ("spi: mediatek: Add spi bus for Mediatek MT8173") Signed-off-by: Peter Hess peter.hess@ph-home.de Signed-off-by: Frank Wunderlich frank-w@public-files.de Link: https://lore.kernel.org/r/20210706121609.680534-1-linux@fw-web.de Signed-off-by: Mark Brown broonie@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/spi/spi-mt65xx.c | 16 +++++++++++++--- 1 file changed, 13 insertions(+), 3 deletions(-)
diff --git a/drivers/spi/spi-mt65xx.c b/drivers/spi/spi-mt65xx.c index 5d643051bf3d..8f2d112f0b5d 100644 --- a/drivers/spi/spi-mt65xx.c +++ b/drivers/spi/spi-mt65xx.c @@ -434,13 +434,23 @@ static int mtk_spi_fifo_transfer(struct spi_master *master, mtk_spi_setup_packet(master);
cnt = xfer->len / 4; - iowrite32_rep(mdata->base + SPI_TX_DATA_REG, xfer->tx_buf, cnt); + if (xfer->tx_buf) + iowrite32_rep(mdata->base + SPI_TX_DATA_REG, xfer->tx_buf, cnt); + + if (xfer->rx_buf) + ioread32_rep(mdata->base + SPI_RX_DATA_REG, xfer->rx_buf, cnt);
remainder = xfer->len % 4; if (remainder > 0) { reg_val = 0; - memcpy(®_val, xfer->tx_buf + (cnt * 4), remainder); - writel(reg_val, mdata->base + SPI_TX_DATA_REG); + if (xfer->tx_buf) { + memcpy(®_val, xfer->tx_buf + (cnt * 4), remainder); + writel(reg_val, mdata->base + SPI_TX_DATA_REG); + } + if (xfer->rx_buf) { + reg_val = readl(mdata->base + SPI_RX_DATA_REG); + memcpy(xfer->rx_buf + (cnt * 4), ®_val, remainder); + } }
mtk_spi_enable_transfer(master);